Hello. I am stuck in Bunkam Lagoon. I got both marbles but when I got the second one, the animation showed only one marble floating where the mask was and no mask. When I climb up to where the mask and door should be there is no mask or door. The Queen is telling me to go through the door, but there is no door to go through! Attached a screenshot to explain what I'm seeing.
Anyone else had this happen? Any way to get the level to re-load correctly with the mask, both marbles and the door?
Currently this is a game-breaking glitch as I cannot progress any further.
Anyone have any suggestions?

Wow. That's a crazy glitch. It has never happened to me. Unfortunately, your Story profile may be corrupted. Sorry. I'd say to wait for a patch and reset your story mode progress if a fix for this problem never comes out. :/

I have the same problem but with oddsock. I have gotten all 3 marbles but the monument they should go into and the door to unlock oddsock are not there in manglewood. If I go to that area I just fall through the ground and die. did you ever find a way to move foreword?

Your best bet is to not continue the story or reset your profile.

Same here. Lagoon and Manglewood broken. Finished Manglewood obviously, came back to collect stuff, but won't work. Can't finish Lagoon and thus the game.

How can I reset my story mode?? I want to try starting over from scratch but don't know how to reset my progress.??????

Maybe you could reset the story mode progress by deleting the LBP3 content in the PS4 menu: settings - application saved data management - saved data in system storage.
...I won't assume any liability!!!!